Protocol · Infectious/Respiratory
Lower Respiratory Tract Infection Support Protocol
Vitamin C and Vitamin D are the core of this stack, with 3 supporting supplements. Each row gives the amount the protocol lists and the grade our evidence database holds for that supplement in Lower Respiratory Tract Infection Support.
We are re-verifying the studies cited on protocol pages; only confirmed citations are shown.
The stack
5 supplements · 1 graded
| Grade | Supplement | Amount listed | Why it’s in the stack | Evidence on file | Shop |
|---|---|---|---|---|---|
| Primary stackThe core of this protocol | |||||
| Vitamin C | Amount listed: 1,000–2,000 mg daily during infection | Supports immune function; may reduce severity and duration of respiratory infections
| Not graded yet | ||
| Vitamin D | Amount listed: 2,000–4,000 IU daily | Supports immune function; deficiency increases infection risk
| Grade D for Lower Respiratory Tract Infection Risk5,110 people | ||
| Supporting stackListed as additions to the core | |||||
| Zinc | Amount listed: 15–30 mg daily | Supports immune response to infections | Not graded yet | ||
| Probiotics | Amount listed: 10–20 billion CFU daily | May reduce duration of respiratory infections; supports immune function | Not graded yet | ||
| N-Acetyl Cysteine | Amount listed: 600–1,200 mg daily | Mucolytic; helps thin mucus and supports lung health | Not graded yet | ||
Shop the evidence-backed picks
Support alongside medical care. These supplements are not a treatment for Lower Respiratory Tract Infection. If you are being treated for it, talk to your clinician before adding one: supplements can interact with medicines.
The collection holds the supplements we grade A or B for its theme, in third-party tested products where the catalog has them. It opens in our Fullscript store. You can look through it without signing in; Fullscript asks for a free account to order.
Or shop one supplement
Each opens third-party tested products, matched to the dose above where we can.
- Grade D
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How this protocol works
In plain language
Lower respiratory tract infections (LRTIs) affect the airways below the voice box - the bronchi and lungs. They include bronchitis, bronchiolitis, and pneumonia.
TYPES:
- Acute bronchitis (most common in adults)
- Bronchiolitis (common in infants - usually RSV)
- Pneumonia (lung infection)
- Influenza with lower respiratory involvement
SYMPTOMS:
- Cough (may produce mucus)
- Shortness of breath
- Wheezing
- Chest discomfort or pain
- Fever
- Fatigue
- Rapid breathing
CAUSES:
- Viral (most common - influenza, RSV, adenovirus)
- Bacterial (Streptococcus pneumoniae, H. influenzae, Mycoplasma)
CRITICAL: See a doctor for:
- High fever (>103°F/39.4°C)
- Difficulty breathing
- Blue lips or fingernails
- Coughing up blood
- Symptoms worsening after initial improvement
- Elderly or immunocompromised patients
MEDICAL TREATMENT:
- Antibiotics (if bacterial)
- Antivirals (for influenza)
- Bronchodilators
- Oxygen if needed
- Hospitalization for severe cases
Vitamin C and D* support immune function.
NAC* helps with mucus clearance.
Bacterial pneumonia requires antibiotics.*
Expected timeline: Acute bronchitis: 1-3 weeks. Pneumonia: 1-4 weeks depending on severity. Supplements support recovery.